Other ADC drugs, such as RC48: hertuzumab + valine-citrulline linker + tubulin inhibitor monomethyl auristatin E (MMAE), A166: trastuzumab + valine-citrulline linker + tubulin inhibitor duostatin-5 (Duo-5) and SHR-A1811: trastuzumab + tetrapeptide linker + topoisomerase inhibitor SHR9265 mainly remain at clinical trials, and demonstrate considerable therapeutic effects in the treatment of HER2-positive breast cancer [86,87,88]. This evidence concerns the gene ERBB2 and breast cancer.